350 290hp Crate Engine Upgrades - heads - Photo 25737119

Note the deep, open chamber design of the factory 76cc cylinder heads. With lazy, low-velocity intake ports full of restrictions and a cavernous combustion chamber these heads only just get the job done. In the past, builders would spend hours hogging, milling, and porting just to make the same power you can get out of an uncut set of Vortec heads.